This PR closes [Issue
#13482](https://github.com/nushell/nushell/issues/13482)
# Description
This PR tend to make all math function to be constant.
# User-Facing Changes
The math commands now can be used as constant methods.
### Some Example
```
> const MODE = [3 3 9 12 12 15] | math mode
> $MODE
╭───┬────╮
│ 0 │ 3 │
│ 1 │ 12 │
╰───┴────╯
> const LOG = [16 8 4] | math log 2
> $LOG
╭───┬──────╮
│ 0 │ 4.00 │
│ 1 │ 3.00 │
│ 2 │ 2.00 │
╰───┴──────╯
> const VAR = [1 3 5] | math variance
> $VAR
2.6666666666666665
```
# Tests + Formatting
Tests are added for all of the math command to test there constant
behavior.
I mostly focused on the actual user experience, not the correctness of
the methods and algorithms.
# After Submitting
I think this change don't require any additional documentation. Feel
free to correct me in this topic please.
# Description
The working directory doesn't have to be set for those tests (or would
be the default anyways). When appropriate also remove calls to the
`pipeline()` function. In most places kept the diff minimal and only
removed the superfluous part to not pollute the blame view. With simpler
tests also simplified things to make them more readable overall (this
included removal of the raw string literal).
Work for #8670
* move commands, futures.rs, script.rs, utils
* move over maybe_print_errors
* add nu_command crate references to nu_cli
* in commands.rs open up to pub mod from pub(crate)
* nu-cli, nu-command, and nu tests are now passing
* cargo fmt
* clean up nu-cli/src/prelude.rs
* code cleanup
* for some reason lex.rs was not formatted, may be causing my error
* remove mod completion from lib.rs which was not being used along with quickcheck macros
* add in allow unused imports
* comment out one failing external test; comment out one failing internal test
* revert commenting out failing tests; something else might be going on; someone with a windows machine should check and see what is going on with these failing windows tests
* Update Cargo.toml
Extend the optional features to nu-command
Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>